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Yuang-seng Tsuei - One of the best experts on this subject based on the ideXlab platform.
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treating cerebrovascular diseases in hybrid operating room equipped with a robotic angiographic Fluoroscopy System level of necessity and 5 year experiences
Acta Neurochirurgica, 2019Co-Authors: Chihhsiang Liao, Wenhsien Chen, Shihchieh Shen, Yuang-seng TsueiAbstract:BACKGROUND: A hybrid operating room (OR) equipped with robotic angiographic Fluoroscopy System has become prevalent in neurosurgery. The level of necessity of the hybrid OR in treating cerebrovascular diseases (CVD) is rarely discussed. OBJECTIVE: The authors proposed a scoring and classification System to evaluate the cerebrovascular procedures according to the level of treatment necessity for CVD in a hybrid OR and shared our 5-year experiences. METHODS: From December 2009 to January 2016, the registry of cerebrovascular procedures performed in the hybrid OR was retrieved. A scoring System was used to evaluate the importance of the surgical and interventional components of a cerebrovascular procedure performed in the hybrid OR. The score of either component ranged from 1, 1.5, to 2 (1 = no role, 1.5 = supplementary or informative, 2 = important or therapeutic). The total score of a procedure was by multiplying two individual scores. Levels of necessity were classified into level A (important), level B (beneficial), and level C (replaceable). RESULTS: A total of 1027 cerebrovascular procedures were performed during this period: diagnostic angiography in 328, carotid artery stenting in 286, aneurysm coiling in 128, intra-operative DSA in 101, aspiration of ICH under image guidance in 79, intra-arterial thrombolysis/thrombectomy in 51, intracranial angioplasty/stenting in 30, hybrid surgery/serial procedures in 19, and rescue surgery during embolization in 5. According to the scoring System, hybrid surgery and serial procedures scored the highest points (2 × 2). The percentages distributed at each level: levels A (2.3%), B (17.5%), and C (80.2%). CONCLUSION: This study conveys a concept of what a hybrid OR equipped with robotic angiographic Fluoroscopy System is capable of and its potential. For cerebrovascular diseases, hybrid OR exerts its value via hybrid surgery or avoiding patient transportation in serial procedures (level A), via providing real-time high-quality angiography and image guidance (level B), which constituted about 20% of the cases. The subspecialty of the group using the hybrid OR directly reflects on the number of procedures categorized in each level. In a hybrid OR, innovative treatment strategies for difficult-to-treat CVD can be developed.
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treating cerebrovascular diseases in hybrid operating room equipped with a robotic angiographic Fluoroscopy System level of necessity and 5 year experiences
Acta Neurochirurgica, 2019Co-Authors: Chihhsiang Liao, Wenhsien Chen, Shihchieh Shen, Yuang-seng Tsuei, Chunghsin LeeAbstract:A hybrid operating room (OR) equipped with robotic angiographic Fluoroscopy System has become prevalent in neurosurgery. The level of necessity of the hybrid OR in treating cerebrovascular diseases (CVD) is rarely discussed. The authors proposed a scoring and classification System to evaluate the cerebrovascular procedures according to the level of treatment necessity for CVD in a hybrid OR and shared our 5-year experiences. From December 2009 to January 2016, the registry of cerebrovascular procedures performed in the hybrid OR was retrieved. A scoring System was used to evaluate the importance of the surgical and interventional components of a cerebrovascular procedure performed in the hybrid OR. The score of either component ranged from 1, 1.5, to 2 (1 = no role, 1.5 = supplementary or informative, 2 = important or therapeutic). The total score of a procedure was by multiplying two individual scores. Levels of necessity were classified into level A (important), level B (beneficial), and level C (replaceable). A total of 1027 cerebrovascular procedures were performed during this period: diagnostic angiography in 328, carotid artery stenting in 286, aneurysm coiling in 128, intra-operative DSA in 101, aspiration of ICH under image guidance in 79, intra-arterial thrombolysis/thrombectomy in 51, intracranial angioplasty/stenting in 30, hybrid surgery/serial procedures in 19, and rescue surgery during embolization in 5. According to the scoring System, hybrid surgery and serial procedures scored the highest points (2 × 2). The percentages distributed at each level: levels A (2.3%), B (17.5%), and C (80.2%). This study conveys a concept of what a hybrid OR equipped with robotic angiographic Fluoroscopy System is capable of and its potential. For cerebrovascular diseases, hybrid OR exerts its value via hybrid surgery or avoiding patient transportation in serial procedures (level A), via providing real-time high-quality angiography and image guidance (level B), which constituted about 20% of the cases. The subspecialty of the group using the hybrid OR directly reflects on the number of procedures categorized in each level. In a hybrid OR, innovative treatment strategies for difficult-to-treat CVD can be developed.
Graeme P Penney - One of the best experts on this subject based on the ideXlab platform.
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remapping of digital subtraction angiography on a standard Fluoroscopy System using 2d 3d registration
Proceedings of SPIE, 2015Co-Authors: Mazen Alhrishy, Andreas Varnavas, Alexis Guyot, Tom Carrell, Andrew P King, Graeme P PenneyAbstract:Fluoroscopy-guided endovascular interventions are being performing for more and more complex cases with longer screening times. However, X-ray is much better at visualizing interventional devices and dense structures compared to vasculature. To visualise vasculature, angiography screening is essential but requires the use of iodinated contrast medium (ICM) which is nephrotoxic. Acute kidney injury is the main life-threatening complication of ICM. Digital subtraction angiography (DSA) is also often a major contributor to overall patient radiation dose (81% reported). Furthermore, a DSA image is only valid for the current interventional view and not the new view once the C-arm is moved. In this paper, we propose the use of 2D-3D image registration between intraoperative images and the preoperative CT volume to facilitate DSA remapping using a standard Fluoroscopy System. This allows repeated ICM-free DSA and has the potential to enable a reduction in ICM usage and radiation dose. Experiments were carried out using 9 clinical datasets. In total, 41 DSA images were remapped. For each dataset, the maximum and averaged remapping accuracy error were calculated and presented. Numerical results showed an overall averaged error of 2.50 mm, with 7 patients scoring averaged errors < 3 mm and 2 patients < 6 mm.
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interventional digital tomosynthesis from a standard Fluoroscopy System using 2d 3d registration
Medical Image Analysis, 2015Co-Authors: Mazen Alhrishy, Andreas Varnavas, Tom Carrell, Andrew P King, Graeme P PenneyAbstract:Interventional Fluoroscopy provides guidance in a variety of minimally invasive procedures. However, three-dimensional (3D) clinically relevant information is projected onto a two-dimensional (2D) image which can make image interpretation difficult. Moreover, vasculature visualisation requires the use of iodinated contrast media which is nephrotoxic and is the primary cause of renal complications. In this article, we demonstrate how digital tomosynthesis slices can be produced on standard Fluoroscopy equipment by registering the preoperative CT volume and the intraoperative Fluoroscopy images using 2D-3D image registration. The proposed method automatically reconstructs patient-anatomy-specific slices and removes clutter resulting from bony anatomy. Such slices could provide additional intraoperative information which cannot be provided by the preoperative CT volume alone, such as the deformed aorta position offering improved guidance precision. Image acquisition would fit with interventional clinical work-flow and would not require a high X-ray dose. Experiments are carried out using one phantom and four clinical datasets. Phantom results showed a 3351% contrast-to-noise improvement compared to standard Fluoroscopy. Patient results showed our method enabled visualization of clinically relevant features: outline of the aorta, the aortic bifurcation and some aortic calcifications.
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interventional digital tomosynthesis from a standard Fluoroscopy System using 2d 3d registration
Medical Image Computing and Computer-Assisted Intervention, 2013Co-Authors: Mazen Alhrishy, Andreas Varnavas, Tom Carrell, Andrew P King, Graeme P PenneyAbstract:Fluoroscopy is the mainstay of interventional radiology. However, the images are 2D and visualisation of vasculature requires nephrotoxic contrast. Cone-beam computed tomography is often available, but involves large radiation dose and interruption to clinical workflow. We propose the use of 2D-3D image registration to allow digital tomosynthesis (DTS) slices to be produced using standard Fluoroscopy equipment. Our method automatically produces patient-anatomy-specific slices and removes clutter resulting from bones. Such slices could provide additional intraoperative information, offering improved guidance precision. Image acquisition would fit with interventional clinical workflow and would not require a high x-ray dose. Phantom results showed a 1133% contrast-to-noise improvement compared to standard Fluoroscopy. Patient results showed our method enabled visualisation of clinically relevant features: outline of the aorta, the aortic bifurcation and some aortic calcifications.
Michael A Speidel - One of the best experts on this subject based on the ideXlab platform.
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depth resolved registration of transesophageal echo to x ray Fluoroscopy using an inverse geometry Fluoroscopy System
Medical Physics, 2015Co-Authors: Charles R Hatt, Michael T Tomkowiak, David Dunkerley, Jordan M Slagowski, Tobias Funk, Amish N Raval, Michael A SpeidelAbstract:Purpose: Image registration between standard x-ray Fluoroscopy and transesophageal echocardiography (TEE) has recently been proposed. Scanning-beam digital x-ray (SBDX) is an inverse geometry Fluoroscopy System designed for cardiac procedures. This study presents a method for 3D registration of SBDX and TEE images based on the tomosynthesis and 3D tracking capabilities of SBDX. Methods: The registration algorithm utilizes the stack of tomosynthetic planes produced by the SBDX System to estimate the physical 3D coordinates of salient key-points on the TEE probe. The key-points are used to arrive at an initial estimate of the probe pose, which is then refined using a 2D/3D registration method adapted for inverse geometry Fluoroscopy. A phantom study was conducted to evaluate probe pose estimation accuracy relative to the ground truth, as defined by a set of coregistered fiducial markers. This experiment was conducted with varying probe poses and levels of signal difference-to-noise ratio (SDNR). Additional phantom and in vivo studies were performed to evaluate the correspondence of catheter tip positions in TEE and x-rayimages following registration of the two modalities. Results: Target registration error (TRE) was used to characterize both pose estimation and registration accuracy. In the study of pose estimation accuracy, successful pose estimates (3D TRE < 5.0 mm) were obtained in 97% of cases when the SDNR was 5.9 or higher in seven out of eight poses. Under these conditions, 3D TRE was 2.32 ± 1.88 mm, and 2D (projection) TRE was 1.61 ± 1.36 mm. Probe localization error along the source-detector axis was 0.87 ± 1.31 mm. For the in vivo experiments, mean 3D TRE ranged from 2.6 to 4.6 mm and mean 2D TRE ranged from 1.1 to 1.6 mm. Anatomy extracted from the echo images appeared well aligned when projected onto the SBDX images. Conclusions: Full 6 DOF image registration between SBDX and TEE is feasible and accurate to within 5 mm. Future studies will focus on real-time implementation and application-specific analysis.
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three dimensional tracking of cardiac catheters using an inverse geometry x ray Fluoroscopy System
Medical Physics, 2010Co-Authors: Michael A Speidel, Michael T Tomkowiak, Amish N Raval, Michael S Van LyselAbstract:Purpose: Scanning beam digital x-ray (SBDX) is an inverse geometry fluoroscopic System with high dose efficiency and the ability to perform continuous real-time tomosynthesis at multiple planes. This study describes a tomosynthesis-based method for 3D tracking of high-contrast objects and present the first experimental investigation of cardiac catheter tracking using a prototype SBDX System. Methods: The 3D tracking algorithm utilizes the stack of regularly spaced tomosynthetic planes that are generated by SBDX after each frame period (15 frames/s). Gradient-filtered versions of the image planes are generated, the filtered images are segmented into object regions, and then a 3D coordinate is calculated for each object region. Two phantom studies of tracking performance were conducted. In the first study, an ablation catheter in a chest phantom was imaged as it was pulled along a 3D trajectory defined by a catheter sheath (10, 25, and 50 mm/s pullback speeds). SBDX tip tracking coordinates were compared to the 3D trajectory of the sheath as determined from a CT scan of the phantom after the registration of the SBDX and CT coordinate Systems. In the second study, frame-to-frame tracking precision was measured for six different catheter configurations as a function of image noise level (662-7625more » photons/mm{sup 2} mean detected x-ray fluence at isocenter). Results: During catheter pullbacks, the 3D distance between the tracked catheter tip and the sheath centerline was 1.0{+-}0.8 mm (mean {+-}one standard deviation). The electrode to centerline distances were comparable to the diameter of the catheter tip (2.3 mm), the confining sheath (4 mm outside diameter), and the estimated SBDX-to-CT registration error ({+-}0.7 mm). The tip position was localized for all 332 image frames analyzed and 83% of tracked positions were inside the 3D sheath volume derived from CT. The pullback speeds derived from the catheter trajectories were within 5% of the programed pullback speeds. The tracking precision of ablation and diagnostic catheter tips ranged from {+-}0.2 mm at the highest image fluence to {+-}0.9 mm at the lowest fluence. Tracking precision depended on image fluence, the size of the tracked catheter electrode, and the contrast of the electrode. Conclusions: High speed multiplanar tomosynthesis with an inverse geometry x-ray Fluoroscopy System enables 3D tracking of multiple high-contrast objects at the rate of fluoroscopic imaging. The SBDX System is capable of tracking electrodes in standard cardiac catheters with approximately 1 mm accuracy and precision.« less
Greg A Fleming - One of the best experts on this subject based on the ideXlab platform.
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variability in radiation dose and image quality a comparison across Fluoroscopy System vendors generations of equipment and institutions
Catheterization and Cardiovascular Interventions, 2018Co-Authors: Kevin D Hill, Steve D Mann, Michael P Carboni, Thomas P Doyle, Salim F Idriss, Dana Janssen, George T Nicholson, Shyam Sathanandam, Greg A FlemingAbstract:Objectives To evaluate differences in radiation dose and image quality across institutions, fluoroscope vendors and generations of fluoroscopes for pediatric cardiac catheterization. Background Increased recognition of the potentially harmful effects of ionizing radiation has spurred technological advances in fluoroscopes, as well as increased focus on optimizing fluoroscope performance. There is currently little understanding of variability in the dose-image quality relationship across institutions, fluoroscope vendor and/or generation of equipment. Methods We evaluated latest generation fluoroscopes from Phillips, Siemens, GE, and Toshiba, and an older generation Phillips fluoroscope (release date 2003) at three different institutions. Radiation dose was measured using an anthropomorphic dose-assessment phantom with effective dose in mSv estimated from Monte Carlo simulations. Image quality phantom images were scored on a 12-point scale by three blinded reviewers. Results Fluoroscope effective doses ranged from 0.04 to 0.14 mSv/1,000 pulses for Fluoroscopy with associated composite image quality scores ranging from 8.0 ± 0.6 to 10.4 ± 1.3. For cineangiography, effective doses ranged from 0.17 to 0.57 mSv/1,000 frames with image quality scores ranging from 10.1 ± 0.3 to 11.1 ± 0.3. There was modest correlation between effective dose and image quality (r = 0.67, P = 0.006). The older generation fluoroscope delivered consistently higher doses than the newer generation Systems (2.3- to 3.5-fold higher for Fluoroscopy; 1.1- to 3.4-fold higher for cineangiography) without appreciable differences in image quality. Conclusion Technological advances have markedly improved fluoroscope performance. Comparing latest generation Systems across vendors and institutions, we found variability in the dose-IQ relationship and speculate that this reflects both equipment and institutional optimization practices.
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abstract 12670 variability in radiation dose and image quality a comparison across Fluoroscopy System vendors and generations of equipment
Circulation, 2016Co-Authors: Kevin D Hill, Steve D Mann, Michael P Carboni, Thomas P Doyle, Salim F Idriss, George T Nicholson, Shyam Sathanandam, Dana R Janssen, Greg A FlemingAbstract:Introduction: Increased recognition of the potentially harmful effects of ionizing radiation has spurred technological advances to reduce exposure during Fluoroscopy. However there is currently little understanding of the dose-image quality (IQ) relationship between Fluoroscopy vendors and across generations of equipment used for imaging during pediatric catheterization. Methods: We evaluated latest generation Fluoroscopy Systems from Phillips, Siemens, GE and Toshiba, and an older generation Phillips System (2004 release). Fluoroscopy and cineangiography were performed on a tissue simulation anthropomorphic phantom using a standardized imaging approach. Phantom surface exposures were used for Monte Carlo simulations to calculate radiation effective dose, accounting for differences in beam parameters. We also imaged a Fluoroscopy IQ phantom to assess contrast-detail and line-per-inch visualization. IQ images were scored by 3 blinded reviewers with scores averaged to produce a composite rating (scale 0-18). To assess the impact of imaging approach we then simulated a neonatal cardiac catheterization incorporating “typical” imaging protocols provided by institutions using the various Systems. Results: Effective doses and IQ scores are summarized in the table. Effective doses varied by >400% with the older generation System consistently delivering markedly higher doses. The associated figure summarizes dose and IQ for a simulated neonatal cardiac catheterization which accounts for measured doses as well as the reported institutional imaging parameters summarized in the figure legend. Conclusion: These data demonstrate substantial technological improvements in Fluoroscopy equipment and may be useful to justify institutional “upgrades”. Comparing latest generation Systems across vendors and institutions, we found variability in the dose-IQ relationship that reflects both equipment and imaging approach.
Mazen Alhrishy - One of the best experts on this subject based on the ideXlab platform.
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remapping of digital subtraction angiography on a standard Fluoroscopy System using 2d 3d registration
Proceedings of SPIE, 2015Co-Authors: Mazen Alhrishy, Andreas Varnavas, Alexis Guyot, Tom Carrell, Andrew P King, Graeme P PenneyAbstract:Fluoroscopy-guided endovascular interventions are being performing for more and more complex cases with longer screening times. However, X-ray is much better at visualizing interventional devices and dense structures compared to vasculature. To visualise vasculature, angiography screening is essential but requires the use of iodinated contrast medium (ICM) which is nephrotoxic. Acute kidney injury is the main life-threatening complication of ICM. Digital subtraction angiography (DSA) is also often a major contributor to overall patient radiation dose (81% reported). Furthermore, a DSA image is only valid for the current interventional view and not the new view once the C-arm is moved. In this paper, we propose the use of 2D-3D image registration between intraoperative images and the preoperative CT volume to facilitate DSA remapping using a standard Fluoroscopy System. This allows repeated ICM-free DSA and has the potential to enable a reduction in ICM usage and radiation dose. Experiments were carried out using 9 clinical datasets. In total, 41 DSA images were remapped. For each dataset, the maximum and averaged remapping accuracy error were calculated and presented. Numerical results showed an overall averaged error of 2.50 mm, with 7 patients scoring averaged errors < 3 mm and 2 patients < 6 mm.
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interventional digital tomosynthesis from a standard Fluoroscopy System using 2d 3d registration
Medical Image Analysis, 2015Co-Authors: Mazen Alhrishy, Andreas Varnavas, Tom Carrell, Andrew P King, Graeme P PenneyAbstract:Interventional Fluoroscopy provides guidance in a variety of minimally invasive procedures. However, three-dimensional (3D) clinically relevant information is projected onto a two-dimensional (2D) image which can make image interpretation difficult. Moreover, vasculature visualisation requires the use of iodinated contrast media which is nephrotoxic and is the primary cause of renal complications. In this article, we demonstrate how digital tomosynthesis slices can be produced on standard Fluoroscopy equipment by registering the preoperative CT volume and the intraoperative Fluoroscopy images using 2D-3D image registration. The proposed method automatically reconstructs patient-anatomy-specific slices and removes clutter resulting from bony anatomy. Such slices could provide additional intraoperative information which cannot be provided by the preoperative CT volume alone, such as the deformed aorta position offering improved guidance precision. Image acquisition would fit with interventional clinical work-flow and would not require a high X-ray dose. Experiments are carried out using one phantom and four clinical datasets. Phantom results showed a 3351% contrast-to-noise improvement compared to standard Fluoroscopy. Patient results showed our method enabled visualization of clinically relevant features: outline of the aorta, the aortic bifurcation and some aortic calcifications.
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interventional digital tomosynthesis from a standard Fluoroscopy System using 2d 3d registration
Medical Image Computing and Computer-Assisted Intervention, 2013Co-Authors: Mazen Alhrishy, Andreas Varnavas, Tom Carrell, Andrew P King, Graeme P PenneyAbstract:Fluoroscopy is the mainstay of interventional radiology. However, the images are 2D and visualisation of vasculature requires nephrotoxic contrast. Cone-beam computed tomography is often available, but involves large radiation dose and interruption to clinical workflow. We propose the use of 2D-3D image registration to allow digital tomosynthesis (DTS) slices to be produced using standard Fluoroscopy equipment. Our method automatically produces patient-anatomy-specific slices and removes clutter resulting from bones. Such slices could provide additional intraoperative information, offering improved guidance precision. Image acquisition would fit with interventional clinical workflow and would not require a high x-ray dose. Phantom results showed a 1133% contrast-to-noise improvement compared to standard Fluoroscopy. Patient results showed our method enabled visualisation of clinically relevant features: outline of the aorta, the aortic bifurcation and some aortic calcifications.